We've recently switched to a new AsteriskNow server and I'm seeing allot of "HDLC Abort (6)" in my CLI and after a few times I get a warning that says "chan_dahdi.c:7572 handle_alarms: Detected alarm on channel 2: Yellow Alarm", when this happens we cannot make or receive any calls.

We have a B410P PCI card installed and running on the latest AsteriskNow 13 and FreePBX Distro 6.12.65-26.

I've found a few pages where people describe similar problems but none of them were really helpfull, Is there someone who was able to fix this issue?

On our old server we were using mISDN to configure the Digium card, is it posible to replace DAHDI with mISDN on FreePBX? If so, how?!?!

If it works some of the time, I would say you had a hardware problem (including cabling faults). The best place to get support from is probably the vendor of your interface hardware. This mailing list only deals with the open source software.

I don't think is a hardware or cabling problem since the old server is working fine and have the same hardware (we even swiched out card).

It might be that our telco brings the L1 down, because in the documentation of our old system that runs on an old Asterisk using mISDN instead of DAHDI the person describes that he configured "pmp_l1_check=no" to make sure that the call is always place even if layer is inactive. Is there something similar in the DAHDI configuration to do this?

It might be that our telco brings the L1 down, because in the documentation of our old system that runs on an old Asterisk using mISDN instead of DAHDI the person describes that he configured "pmp_l1_check=no" to make sure that the call is always place even if layer is inactive. Is there something similar in the DAHDI configuration to do this?

However, by default though the B410P will try to bring up layer1 when it detects that the remote side has brought it down. If your telco requires that you allow it to go down (there are some that do) then you should make sure to set in /etc/modprobe.d/dahdi.conf "options wcb4xxp persistentlayer1=0" is set.

persistentlayer1=0 combined with layer1_presence=ignore in chan_dahdi.conf will allow the B410P module to work in an environment where the telco wants to let the spans idle when not in use.